Single acting ON-OFF valve. it is air to open. when sov energized , valve will be open, so during that if air fail then what will be the condition of valve ( open or close ) ???
Answers were Sorted based on User's Feedback
Answer / ahmed
the valve will close because air is fail then only one force is available the spring force the valve will follow spring power even if sov still energized
Is This Answer Correct ? | 13 Yes | 0 No |
Answer / prem
Since SOV is energized theoretically valve will not close. To depressurize the actuator/valve SOV must de energize to open the vent port.
In Other whand,if pneumatic source become empty and no back up supply, Valve will close gradually due to loss of instrument air supply even though SOV is energized.
Is This Answer Correct ? | 5 Yes | 1 No |
Answer / kausar
If it has airlock then it will be remain same because at the time of pneumatic failure it locks the air automatically.generally now with control valve airlock,booster ,sov and air filter regulator are arranged in order to make the line safe
Is This Answer Correct ? | 1 Yes | 1 No |
It will be remain in same condition if there is no air leakage and the valve is not spring loaded.
Is This Answer Correct ? | 1 Yes | 1 No |
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